Mũmbi is a mythological figure regarded as the mother of the Gĩkũyũ people. The word Mũmbi can be translated as "one who moulds". She was the wife of Gĩkũyũ, and ancestor to all the Agĩkũyũ people. The story of Gĩkũyũ and Mũmbi has been recorded by various writers throughout the Gĩkũyũ history; notable among them are Jomo Kenyatta, the first president of independent Kenya, Louis Leakey and the prolific Gĩkũyũ writer Gakaara wa Wanjaũ and another Gĩkũyũ writer known as Mathew Njoroge Kabetũ among many others. The name Mumbi is not purely a Kikuyu name. It is also widely used by the Kamba ethinic community. Among the Kamba community the name carries the same meaning as among the Kikuyu's.
The story of the origin of the Agĩkũyũ:
God (Ngai or Mũgai – The Divider) created Gĩkũyũ the father of the tribe and took him on top of Kĩrĩ-Nyaga (Mount Kenya) and showed him all the land that he had given him: West from Mount Kenya to the Aberdares, on to Ngong Hills and Kilimambogo, then north to Garba Tula. He then pointed to him a spot full of fig trees (Mũkũyũ) and he commanded him to descend and establish his homestead on the selected spot known as Mũkũrwe wa Gathanga (in present-day Muranga County). When Gĩkũyũ descended to the spot he found a beautiful wife waiting for him, Mũmbi. Together, Gĩkũyũ and Mũmbi had nine beautiful daughters: Wanjirũ, Wambũi, Wanjikũ, Wangũi aka Waithiegeni, Wangeci aka Waithĩra, Wanjeeri aka Waceera, Nyambura aka Wakĩũrũ, Wairimũ aka Gathiigia, Wangarĩ and Wamũyũ aka Warigia, which are also very popular names for Gikũyũ females today.
When the time came for the 9 eldest daughters to marry, the youngest Wamũyũ not yet being of age, Gĩkũyũ prayed to God under a holy fig tree (Mũkũyũ, some say Mũgumo), as was his tradition, to send him sons-in-law. He offered a lamb as sacrifice and as the fire was consuming the lamb’s body, nine men appeared and walked out of the flames. Gĩkũyũ took them home and each daughter married the man who was the same height as she was, and together they gave rise to the nine of the full-nine clans to which all Gĩkũyũs belong. Wamũyũ or Warigia got a child out of wedlock. These clans are the Anjirũ, Agacikũ, Ambũi, Angũi aka Aithiegeni, Angechi aka Aithĩrandũ, Aacera, Ambura aka Aakĩũrũ aka Eethaga, Airimũ aka Agathiigia, Angarĩ aka Aithekahuno and Aicakamũyũ.